Custom apps refer to apps that are not in the Teams or Office App Store. Users can add apps to Teams by uploading an app package (also called sideloading) directly into Teams. Sideloading apps is frequently used during the development process to test apps that may not be ready for broader distribution.
To add an app to Teams, the app should first be packaged as a .ZIP file and then uploaded with the following procedure:
- From the Teams interface, expand the ellipsis on the left-hand side rail and select More apps:
- Select Upload a custom app and then Upload:
- Browse to the location of the ZIP file and click Open. The package will be uploaded and then selectable so that it can be added to teams.
Three settings control the uploading of custom apps:
- User custom app policy
- Team custom app setting
- Org-wide custom app setting
Both the User and Org-wide custom app settings are managed in the Microsoft Teams admin center. The Team custom app setting is per-team.
We'll explore each of these configuration settings in the following sections.